Fortunately, Ohio may not be as signficant as it was in 04....not that I wouldnt like to see him carry the state.
Assuming Obama holds all the blue states from 04 (and none are really in danger)....he only need to win Iowa (red in 04), which has been conceded to him, and only one of these scenarios:
...Virginia, where is up by 7%.
or
...Colorado and New Mexico, where he is up by 6% in both
or Colorado and Nevada
or
...Florida, where he is up by from 3-5%
or
... Missouri, where it is a toss up
or
...North Carolina, where he is inching ahead
Any one of those and Obama breaks the 270 electoral barrier. McCain really needs to win all these states....and red states like Indiana and West Virginia are still in play ...creating even more scenarios for an Obama electoral win.
Another reminder of why the national poll numbers are meaningless.
-----Added 17/10/2008 at 01 : 55 : 49-----
Here is this wildest scenario:
MCain pulls out all of the red states where he is trailing -CO, NC, and VA, toss up states -FL and OH, and those states where he is slightly ahead - IN, MO and WV
...and Obama wins NM and NV:
Electoral votes - 269-269
The best possible (but not likely) scenario for Obama:
380 electoral votes to McCain's 158...
an overwhelming mandate that would change the political dynamics of the country...at least for the next four years.